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Help stop experiments on wild-caught owl monkeys in Colombia

Colombian animal researcher, Manuel Elkin Patarroyo, accused of involvement in illegal trafficking of his monkey victims.

Patarroyo (who apparently claims his work is worthy of a Nobel Prize) has been using wild-caught owl (night) monkeys for his malaria research for several years.
However, recently a Colombian news magazine, Cambio, has reported that the local environment authority, Corporación para el Desarrollo Sostenible del Sur de la Amazonía (Corpoamazonia), has initiated an inquiry based on complaints of irregularities at Patarroyo´s research centre, Colombian Immunology Foundation Institute FIDIC. Allegations include animals illegally transferred across borders and reports from a laboratory vet and local officials criticising conditions at the lab and the treatment of the animals, including capture methods.

In 1994, when speaking of a malaria vaccine (SPf66) he had developed Patarroyo proclaimed “...the vaccine is already one of the most important milestones of the history of parasitology”[1]. Unfortunately, the vaccine did not prevent malaria. A report in medical journal The Lancet said “the SPf66 vaccine did not attenuate the clinical manifestations or severity of falciparum malaria and did not reduce the proportion of cases that were symptomatic”. It concluded “The overall estimates of SPf66 vaccine efficiency were not significantly different from zero”[2]. The manufacture of a vaccine with no significant effect cost the lives of countless owl monkeys, often captured illegally, from the rainforests.

One member of Patarroyo’s research team, vet Lina María Peláez reportedly resigned because of “the ecological damage caused by people who, without previous training, capture monkeys of the species Aotus nancymae in an indiscriminate way, and destroy primary forests….” She also claimed of Patarroyo’s “lack of permission to experiment with this species”, and that such actions could have a catastrophic affect on local owl monkey populations, especially since there has been no study of population dynamics nor a programme to reproduce the owl monkeys. Patarroyo’s use of young animals could leave the wild population without enough animals to sustain itself.

Local government officials inspected the lab in 2007, reporting animals in appalling health, animals exceeding their stay, and that there was no rehabilitation plan for those released back into the forest. They reported “the majority of animals had been brought from Peru and Bolivia, without authorization”.

A Peruvian hunter who captures monkeys for the lab told a reporter, “The monkeys are elusive... in order to capture them we have to take down 30 metres of forest around the tree where they are located.. At dawn, we must take the animals, hidden, to Leticia, this way we can avoid the authorities”. Cambio claims to have access to documents, such as internal records from FIDIC and Corpoamazonia’s findings for 2004-5, which demonstrate that they receive and use animals from neighbouring countries such as Peru and Brazil illegally, without the prior authorization of the respective governments.[1]

Marta Bueno, Professor of Biology at Colombia’s National University, was interviewed about Patarroyo’s work with owl monkeys: “… Doctor Patarroyo extracts their spleen and infects them with malaria, in order to determine if the vaccine is effective or not”. She continued “After the experiment, the majority of the animals are liberated in deplorable conditions. This causes later problems for wild populations”[1].

The removal of an animal’s spleen and the subsequent release of the animals into the wild environment is wholly irresponsible, both scientifically and morally.
The spleen has an important role in “immune surveillance and response”[3]. Research in humans has shown that “humans with acute P.falciparum malaria, who had previously undergone splenectomy, had decreased clearance of pRBCs [parasitized red blood cells] from the circulation”[4]. Therefore the animals are not able to fight off diseased as un-splenectomised animals would.

A 1999 article reported that Patarroyo had used “11,500 monkeys”[5]. Since then, thousands more monkeys lives have been destroyed and the environment put in jeopardy by this scientifically discredited research.

  1. Cambio. Los Micos de Patarroyo. – No. 751 22-28/11/07 and Corporación para el Desarrollo Sostenible del Sur de la Amazonía Inquiry File No. 000102,
  2. Nosten, F et al (1996) “Randomised double-blind placebo-controlled trial of SPf66 malaria vaccine in children in northwestern Thailand”, The Lancet, vol.348, pp.701-707
  3. Maireb, E.N. (1992) “Human Anatomy & Physiology”, The Benjamin / Cummings Publishing Company Inc, California.
  4. Engwerda, C.R. et al (2004) “The importance of the spleen in malaria”, TRENDS in parasitology, vol.21, no.2, Feb 2005
  5. Brown, P (1999) “Scientist whose dream of beating disease came true” The Guardian, 24th July

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